Current Affairs Science Projects And Inventions

"The skyscraper establishes the block, the block creates the street, the street offers itself to man." Roland Barthes, literary and social theorist Before the advent of the skyscraper, tall buildings were built to showcase great wealth, power, or religious beliefs. For the architect and civil engineer William Le Baron Jenney (1832-1907), the urge to build great edifices was born from a necessity to solve commercial (and later residential) needs in his native Chicago, where ground space was at a premium. Two obstacles to the construction of highrise buildings were overcome in the mid-nineteenth century, paving the way for the skyscraper. In 1853 Elisha Graves Otis devised a mechanism to prevent elevators from falling if their cable broke, enabling passengers to be transported upward safely. The second breakthrough came with a steel-framed structure that could support the entire weight of its walls, instead of the traditional load-bearing walls that carry the building's weight. Jenney's ten-story Home Insurance Company Building, built in Chicago in 1884 and 1885, was the first to use an internal framework, or skeleton, made from steel columns and girders as well as a curtain wall that was fixed to the steel structure. Architects were soon racing to design bigger skyscrapers, especially in New York where there were no laws restricting height. Since Jenney's design, skyscrapers built with glass have been able to withstand severe weather, including earthquakes. Buildings have incorporated plazas and parks alongside numerous entertainment and consumer venues at street level. Energy conservation is paramount to all future design in the twenty-first century. Today the skyscraper is an increasingly familiar sight, springing forth in growing numbers in cities all across the world.—especially Hong Kong, Shanghai, and Dubai, as well as Chicago once again—shaping the way we live within urban centers. 

“You're talking about desire. The name of that... streetcar that bangs through the Quarter." Tennessee Williams, A Streetcar Named Desire (1951) To this day the tram remains the least glamorous of all methods of public transport, but at least American electrical engineer Stephen Dudley Field (1846-1913) tried to give the humble vehicle a little more pizzazz. Field was not issued with a patent for his system of propelling railway cars by electromagnetism until 1880, even though it had been installed in New York City in 1874 by the twenty-eight-year-old inventor—a man often called the "father of the trolley car." The innovative method of providing electricity to the onboard motor worked by having a dynamo generate a current, which was conveyed via two metal wheels that linked the motor with either one of the rails. The system was pretty ineffective and actually highly dangerous, but it marked an important change in the way that people viewed public transport. In the years between the implementation of the electric streetcar in many U.S. cities in the late 1880s and World War I (1914-1918), it became a very popular way of getting around. Because the electric streetcar traveled significantly faster than any of the other forms of transportation, the notion of commuting became a much more palatable option to city residents. Rather than having to inhabit houses right in the center of the cities, people could now move out along the lines of streetcar routes into the suburbs without causing too much disruption to their daily routine. Although Dudley Field enjoyed great success in his lifetime, collecting more than 200 patents for various inventions, few can appreciate his work since none of them actually bear his name. Imagine—a streetcar named Dudley. 

“It’s essential to recognize that no tool... can approach the vastness of the universe and life itself." Hanz Decoz, numerologist                        In appearance it is a simple piece of metal with a hexagonal cross-section and a ninety-degree bend about three-quarters along its length. Called variously Hex key, Alien key, Alum key, Inbus, and Unbrako key, this uncomplicated device may date back to the 1920s. The Unbrako company developed a hexagonal-head key and screw in the 1920s which went on to become popular in the United States and Britain. During the same decade'it is claimed that Italian Egidio Brugola, founder in 1926 of Brugola manufacturing company, also created a hexagonal- head fastener, which was the foundation for a business that still thrives today. In Italy (unsurprisingly) the Alien key is called the "Brugola." A couple of decades later, in 1943, the Alien Manufacturing company took out a trademark on an "Alien Key"—a name that would become popular in the United States and the United Kingdom. Whatever you choose to call it, however, it is undoubtedly one of the most ubiquitous tools on the planet. Its simplicity is undoubtedly one of the many things that makes it such a popular tool, plus the fact that it is small and lightweight, yet being cast from a solid piece of metal is hard-wearing. Either end of the key can be used, which adds versatility to its use. Used extensively in the motor and bicycle industry because the working part of the hex-screw is protected from the elements, it has also recently found popularity with the rise of the "flat-pack" furniture trade, where, because they are relatively cheap to produce, manufacturers are able to include a hex-key with the furniture. 

U.S. computer scientists Carl Kesselman, lan Foster, and Steve Tuecke had the bright idea that computers could be loosely coupled together to provide massive computing ability just as power stations can be linked to supply extra electricity. With computer grids and power grids the consumer does not have to worry about the source or the location of the input. Different types of computers can be incorporated and these may be located all over the world. Your own computer can be used in a grid when you are asleep, during lunch breaks, or even at random moments during the day when the computer is waiting for input. High-speed interconnections are usually not available and so the system works best on problems where independent calculations can be carried out without the participating processors having to communicate. Needless to say, software has to be carefully designed to check for untrustworthy, malfunctioning, and malicious nodes. It also has to accommodate nodes going off-line at random times. The participating nodes also have to trust the central system not to interfere with their individual programs, security, and data storage. Grid computing is widely used for solving extremely complicated mathematical problems and for specific computing applications where huge amounts of data are involved. The latter include the interrogation of molecular modeling data for pharmaceutical drug design, the analysis of electrical brain activity, the searching of radio telescope receiver output for messages from extraterrestrial civilizations, and the investigation of the outputs of high-energy physics machines, such as the Large Hadron Collider while it looks for new elementary particles. 

"We recognized almost at once that the material was different and that It had potential... “ Lois Plunkett In 1938 research chemist Roy Plunkett (1910-1994) was working at the DuPont Jackson laboratory in New Jersey. He had been trying to improve refrigerants to make them nontoxic and nonflammable. Plunkett and his technician Jack Rebok had produced 100 pounds (45 kg) of tetrafluoroethylene gas (TFE), storing it in cylinders on dry ice. When the time came to use the material, nothing came out of the cylinder, even though it weighed the same as before. The gas had turned into a white powder. Plunkett and others at DuPont found that the substance was quite slippery and proved to be a good lubricant. It was resistant to chemicals and heat, and other substances would not adhere to it. The material was resistant to temperatures as high as 500°F (260°C). Plunkett and his colleagues realized the potential of this new polymer and DuPont set about marketing it. At first Teflon® (the new trade name for this substance) was so expensive that no one seemed interested in purchasing it. However, this slowly changed as the material was used first in military and industrial applications and later in household use, most notably on nonstick pans. Awarded a patent in 1941, Teflon® is used as a coating for fabrics, wires, and metals—three-quarters of the pots and pans sold in the United States are coated with it—and also in industries such as aerospace and pharmaceuticals.

Man has cultivated the Earth for thousands of years, and for a large portion of that time he has been "tilling"—turning the soil to bury weeds and mix in fertilizer—in order to grow crops. Tillage, and agriculture in general, took a big step toward modern intensive processes when Australian inventor Arthur Clifford (Cliff) Howard (1893-1971) created the motorized tiller—the Howard Rotovator—in 1912. The son of a farmer, Howard studied engineering in Australia at Moss Vale, New South Wales. In 1912 he began experimenting on farming methods—primarily machines to improve tillage—on the family farm at Gilgandra, New South Wales. Howard noticed that regular plowing methods compacted the soil, making it more difficult to mix in fertilizer. Rotary tillage already existed, but was operated manually. Howard took a standard manual tiller and coupled it to his father's steam tractor. This proved superior to the standard plowing techniques, taking less effort to run, mixing the soil better and more evenly, and resulting in less crop residue being left on the surface. Howard patented his creation, trademarked the name "Rotavator," and formed Austral Auto Cultivators Pty Ltd. in 1922 to market his invention. Howard went on to develop an extensive line of rotary tillers powered by internal combustion engines for many specific terrains, including orchards and vineyards. He also designed machines that could destroy weeds. Eventually, Howard marketed his machines around the world. Today rotavators are commonly used for soil preparation and are essential for maintaining the high yields of intensive modern agriculture. 

Both waterproof and airtight, cellophane is now used for everything from food packaging to sticky tape. The man who invented it—Swiss textiles engineer Jacques E. Brandenberger (1872-1954)—initially wanted to develop a clear coating for cloth to make it waterproof after witnessing a wine spill on a restaurant tablecloth. He tried coating cloth with a thin sheet of viscose, but viscose made the cloth too stiff. The transparent sheet of film separated easily from the cloth and Brandenberger soon realized that the film itself had more potential than the waterproofed cloth. To create cellophane, Brandenberger dissolved cellulose fibers from materials such as celery, wood, cotton, or hemp in alkali and carbon disulfide to make viscose, which is then extruded through a slit into an acid bath to reconvert the viscose back into cellulose. The acid regenerates the cellulose, which forms a film, and further treatment—for example washing and bleaching—produces cellophane. (Rayon is made by a similar process, but the viscose is extruded through a hole rather than a slit.) Brandenberger named the substance cellophane after "cello," from cellulose, and "phane" from the French word diaphane, meaning transparent. It took the scientist almost a decade to perfect the substance and produce it commercially, and, in 1927, the invention  of a  waterproof lacquer  created moistureproof cellophane, which meant that it could be used to package food. The use of cellophane for packaging has decreased since the 1960s, and DuPont, the company that introduced it to the United States, even discontinued the product in 1986. Yet, despite this, cellophane's 100 percent biodegradability means that it could be due for a comeback. 

Spectrophotometers are used to measure the intensity of electromagnetic radiation. Usually the measurements are confined by filters to a very narrow spectral range and the instrument is used to detect the change in brightness after the light radiation has either passed through a sample or been reflected off it. Early devices used the naked eye to determine the differences in intensity between two beams. Arthur Hardy (1895-1977), a physicist at the Massachusetts Institute of Technology, decided to replace the eye with the new cesium photocells, and thus detect intensities electronically. The plan was to produce a Spectrophotometer that automatically scanned through the visible spectrum and produced a pen-drawn spectrum showing how the light intensity varied with wavelength. Beam splitters and rotating polarizers were used and the two beams were compared by blinking quickly from one to another using a flicker photometer technique. Working in collaboration with the firm General Electric, the first operational production machine was ready by 1935. Soon, the National Bureau of Standards was using Hardy's spectrophotometers to test pigments and dyes and to set paint color standards. The fully automated machine was extremely expensive, and soon cheaper versions were being produced that required manual fixed-point scanning of the spectrum. Spectrophotometers found their way into industrial and scientific laboratories. Similar instruments have been used widely to monitor the seasonal and latitudinal variation of ozone, and a spectrophotometer led to the discovery of the ozone hole over Antarctica. 

"What then is time? If no one asks me, I know what it is. If I wish to explain it, ...I do not know." Saint Augustine, theologian A time zone is a longitude band around the globe in which everyone sets their clocks to the same time— regulated by the movement of the sun. Before time zones were introduced, every town kept its own local time. But with the advent of the railways this system became very inconvenient, as the time at the starting point of a journey might well differ from the one at the terminus. In 1847 the railway companies in Great Britain recommended that all docks should be set using the same time marker. Noon on the Greenwich Meridian (0 degrees longitude) was chosen, which is known as Greenwich Mean Time (G.M.T.). Because Earth spins every twenty-four hours, local time varies by one hour for every 15-degree change in longitude. Scottish-born engineer and inventor Sir Sand ford Fleming (1827-1915) recognized this and suggested that not only should continental America have four meridians, but that similar 15-degree time zones should be established all over the globe. In 1884 the Fleming plan was accepted for the whole world at the International Meridian Conference in Washington, D.C, and the Greenwich Meridian was chosen as the prime meridian. 

Doctors treating polio patients found that while many sufferers were unable to breathe in the acute stage, when the action of the virus paralyzed muscles in the chest, those who survived this stage usually recovered completely. Such observations indicated the need to develop strategies to maintain respiration until the patient could breathe independently again. In 1927, chemical engineers Philip Drinker (1894-1972) and Louis Agassiz Shaw, from Harvard University, devised a tank respirator to maintain respiration. In the device, the patient's head stuck out of the end of the tank, with a sponge rubber seal to make it airtight. Air was then pumped from the tank to produce negative pressure causing the chest to expand and thus produce breathing. The first iron lung was installed in 1927 at Bellevue Hospital, New York, and in 1928 the first patient was an eight-year-old girl with polio, comatosed from lack of oxygen. One minute after the device was switched on, she regained consciousness and asked for ice cream. Further refinements included a garage mechanic's "creeper" that allowed patients to slide out of the tank, and boat "portholes" through which medical staff provided treatment. Equipment designer John Haven Emerson produced an iron lung that could vary the respiration rate, with the added advantage that it cost half as much to manufacture. The iron lung helped to save thousands of lives during the polio outbreaks of the 1940s and 1950s. In 1959, 1,200 people were using tank respirators in the United States, but with the advent of the polio vaccine this figure had fallen to thirty by 2004.